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diff --git a/contrib/llvm-project/libcxx/include/__type_traits/is_trivially_relocatable.h b/contrib/llvm-project/libcxx/include/__type_traits/is_trivially_relocatable.h
index c0871731cc00..9b0e240de55f 100644
--- a/contrib/llvm-project/libcxx/include/__type_traits/is_trivially_relocatable.h
+++ b/contrib/llvm-project/libcxx/include/__type_traits/is_trivially_relocatable.h
@@ -11,7 +11,6 @@
#include <__config>
#include <__type_traits/enable_if.h>
-#include <__type_traits/integral_constant.h>
#include <__type_traits/is_same.h>
#include <__type_traits/is_trivially_copyable.h>
@@ -23,8 +22,11 @@ _LIBCPP_BEGIN_NAMESPACE_STD
// A type is trivially relocatable if a move construct + destroy of the original object is equivalent to
// `memcpy(dst, src, sizeof(T))`.
-
-#if __has_builtin(__is_trivially_relocatable)
+//
+// Note that we don't use the __is_trivially_relocatable Clang builtin right now because it does not
+// implement the semantics of any current or future trivial relocation proposal and it can lead to
+// incorrect optimizations on some platforms (Windows) and supported compilers (AppleClang).
+#if __has_builtin(__is_trivially_relocatable) && 0
template <class _Tp, class = void>
struct __libcpp_is_trivially_relocatable : integral_constant<bool, __is_trivially_relocatable(_Tp)> {};
#else
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